| Pattern | Meaning | Severity |
|---|---|---|
| 1 flash | info | |
| 2 flashes | critical | |
| 3 flashes | high | |
| 4 flashes | high | |
| 5 flashes | critical | |
| 6 flashes | medium | |
| 7 flashes | high | |
| 9 flashes | medium |
| Code | Description | Severity |
|---|---|---|
| 1 Flash | No Previous Error | info |
| 126.02 | High Pressure Alert | warning |
| 126.03 | Low Pressure Alert | warning |
| 126.08 | Compressor Thermal Overload | critical |
| 2 Flash | System Lockout - Retries Exhausted | critical |
| 3 Flash | Pressure Switch Error | high |
| 4 Flash | Open High Limit | high |
| 5 Flash | Flame Sensed Without Gas Valve Call | critical |
| 6 Flash | Power or Low Voltage Interrupt | medium |
| 7 Flash | Gas Valve Circuit Error | high |
| 79 | Low Discharge Temperature | critical |
| 89 | Discharge Temperature Too High | critical |
| 9 Flash | Check Polarity / Ground Fault | medium |
| 91 | Low Evaporator Temp | warning |
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